textproduct: Rapid City

KEY MESSAGES

- Widespread critical fire weather conditions expected through the afternoon.

- Scattered thunderstorms possible over south-central South Dakota Wednesday afternoon and evening. These storms may produce strong wind gusts but not much rain.

- Cool and breezy unsettled weather expected Thursday through the weekend.

DISCUSSION

(This Evening Through Wednesday) Issued at 101 PM MDT Wed Apr 22 2026

Plenty of weather to talk about today that's for sure. For starters, a quick look at the calendar is a good way to remind yourself that it's not June or July but April! Afternoon temps have soared well beyond the normal for late April and have reached the 80s and 90s, which is near 25 to 30 degrees above normal. Strong southerly winds, with gusts upwards of 40 to 50 mph, have helped to usher in that warmer air. To add to this, very low humidities, down to near 10%, means we are seeing critical fire weather conditions around the area. These conditions will last through the early evening. Then temps will cool, humidity will recover, and winds will relax.

The next part of the forecast we are focusing on is the potential for strong to severe thunderstorms later this afternoon and evening. A boundary is tracking through the upper plains and strong to severe storms are possible along that boundary. The main concern for the mode of severe weather is wind gusts. The area of concern for where the storms could pop up is pretty much the all of western SD but higher confidence in the central part of the state, so stay plugged into the weather through the evening for the latest.

Late tonight and Thursday brings a passing cold front, that will swing winds to the west and increase them, again, to gusts upwards of 40 to 50 mph. These westerly winds will usher in cooler air, so expect daily highs to drop to the 40s and 50s. Overnight lows will dip into the 20s to low 30s. Temps like this are below normal for this time of year.

Friday and beyond, the northwest flow will keep an active pattern in place so we are looking at on/off rain or showers to linger in the forecast. And with cold temps at night, any precip we see could fall as a rain/snow mix, or all snow, during the cold times of the day. The higher elevations of the Black Hills have a high chance of seeing accumulating snow Saturday night. Stay plugged into the forecast over the coming days for the details.

AVIATION

(For the 18Z TAFS Through 18Z Thursday) Issued At 1137 AM MDT Wed Apr 22 2026

VFR conditions are generally expected through the TAF period. Isolated/scattered TS may develop after 21z over south-central SD with erratic gusty winds. Gusty southwest winds will diminish tonight, then become strong again out of the northwest late Thursday morning. Some LLWS will be possible overnight over the Black Hills and foothills, including KRAP. Scattered precipitation enters the region Thursday morning as well. Possibly affecting KGCC towards the end of the forecast period.

FIRE WEATHER

Issued At 101 PM MDT Wed Apr 22 2026

Widespread critical fire weather conditions are expected for the rest of the afternoon into early evening. Temperatures have climbed into the 80s and 90s across much of western SD, with humidities as low as 8 to 10%. Southerly winds have increased across the region ahead of an approaching cold front. Reported sustained winds have been upwards of 20 to 30 mph with gusts up to 40 to 50 mph. We are still looking at thunderstorms later this afternoon and evening. These storms aren't expected to produce much rain but will be capable of lightning and strong, erratic wind gusts of 50+ mph.

A cold front will cross the region early Thursday, bringing much cooler temps, rising humidities, and breezy northwest winds (gusts of up to 50 mph across NW SD).

UNR WATCHES/WARNINGS/ADVISORIES

SD... Red Flag Warning until 8 PM MDT /9 PM CDT/ this evening for SDZ319>335. WY...Red Flag Warning until 8 PM MDT this evening for WYZ314>318.